The information in the human genome database promises to provide a new means to investigate human diseases. However, a limiting factor in using this database in identifying new diagnostic/prognostic markers and defining the molecular mechanisms of disease is the challenge of isolating specific cell populations and their mRNA from clinical tissue biopsies Investigators have isolated specific cell types from small samples of tissue using micropipette dissection methods. However, they require a high degree of manual skill and are time-consuming. A Laser Capture Microdissection (LCM) system was developed at NIH to meet this challenge and more rapidly isolate specific cells from clinical biopsy samples. By combining LCM with non-thermophilic RNA amplification methods it is now possible to produce aRNA from 100-1,000 cells and probe high-density arrays for in vivo functional genomic studies of specific cells in clinical biopsies. The Emory Medicine LCM facility will be incorporated into the Vascular Medical Center at Emory University. It will be used to investigate gene expression of specific cell types in a variety of chronic inflammatory diseases such as atherosclerosis, hepatitis C, graft vs. host disease following stem cell transplantation, and studies regarding the in vivo source of actor VIII during chronic liver disease. Specific programs that will utilize the LCM facility include: 1) Comparing gene expression within Kupffer, endothelial stellate, and T cells in liver biopsy samples of control patients and those with chronic hepatitis C (acute vs. chronic; siblings with non-progressive vs. severe progressive inflammation/fibrosis; responders vs. non-responders to treatment); 2) Studying the modulation of gene expression in individual endothelial cells in humans and experimental animals exposed to different hemodynamic milieus and treatments; 3) Studying the in vivo gene expression of vascular adventitial myofibroblasts during post- angioplasty restenosis; 4) Studying the in vivo expression of vascular adventitial myofibroblasts during post-angioplasty restenosis; 4) Studying gene expression of Factor VIII in liver endothelial and parenchyma cells during chronic liver diseases; 5) studying the in vivo gene expression of endothelial cells of proliferating vs. regressing hemangiomas; and 6) studying the in vivo gene expression of human dermal endothelial cells during cutaneous inflammatory diseases.